1	Assessing the Effectiveness of Mine Land Reclamation to Off-Set GHG Emissions Mark Sperow Christopher Bouquot West Virginia University Morgantown, WV 23 March 2005 Presentation at the 2005 USDA Symposium on Greenhouse Gases and Carbon Sequestration in Agriculture and Forestry 21 – 24 March 2005, Baltimore, MD
2	Introduction Since 1977, mine operators required to reclaim disturbed land by planting grass, pasture, or trees (Surface Mining Control and Reclamation Act) Vegetative cover not dictated by SMCRA Little documentation on what is planted Reclaimed mine sites represent a relatively unexplored option for GHG mitigation This study assesses the biophysical potential for C sequestration on reclaimed mine sites Analysis considers reclamation to cropland, pasture, and forest 20 year time period analyzed
3	Background Analysis part of seven state Regional DOE funded study Analyzed land use in IN, KY, MD, MI, OH, PA, and WV Overall objective to identify the potential for C sequestration on cropland, forest, wetland, and mineland to mitigate GHG emissions Land Use areas adjusted to avoid overlap of land area for other uses and mineland
4	Overview C sequestration Pools Above-ground biomass (forest) Forest Litter Layer Forest Soils (0 – 30 cm layers) Pasture Soil (0 – 30 cm layers) Cropland Soil (0 – 30 cm layers) Methods Literature Derived annual C accumulation rates Literature Derived equations from chrono-sequence studies IPCC coefficients (cropland and pasture soil C) Additional Data Sources Surface Permits for coal mines (GIS available for IN, KY, OH, and WV, tabular data only for MD, MI, and PA) 1992 National Land Cover Dataset STATSGO GIS and Tabular to define mineland area
5	Mine Area Data Sources Mine Permit Area – 4 States Indiana Geological Survey Coal Mine Surface shape file –2,615 polygons showing location for mines dating from late 1880 to 2000 Kentucky Series7_boundaries – 1,195 polygons showing mine permit between 1999 to 2002 Ohio Department of Natural Resources Coal Permit Maps - 2,500 polygons showing location of mines between 1975 to 2002 West Virginia Department of Envioronmental Protection Permit Boundaries – 6,100 polygons showing location of mines between 1972 to 2002 National Land Cover data by county
6	Analytical Methods For all land uses, 1992 NLCD primary data source Identify NLCD area defined as mineland Adjust area to account for difference between GIS data for mineland and NLCD Assume average C accumulation from studies of above-ground biomass and litter layer for forest Average soil C accumulation from published studies and IPCC estimates
7	1992 NLCD Landcover Adjusted to Account for Mineland Area after 1992
8	Mine Areas
9	Mine Permit Data for IN, KY, OH and WV
10	Distribution of Mineland
11	Source Data for Carbon Pools Soil Carbon 3 general studies address soil C in forestland 3 studies specifically address soil C on reclaimed mine sites IPCC method (used to assess cropland, pasture, and forest) Forest Litter Layer 2 studies address C content of litter layer in forest 1 study of litter layer for mineland reclaimed to forest Forest Biomass 3 studies address forest growth rates and associated C content 1 study for mineland reclaimed to forest Predominantly USFS studies by state and region
12	How Source Data are Used Considerable variation in C accumulation from published literature Used state specific data when possible Biomass C accumulation rates for states not addressed by published study omitted from mineland C estimates Range of C sequestration estimated using the maximum and minimum rates derived from literature Average rate of C sequestration from all studies provide base values Average C sequestration multiplied by area of mineland
13	Average Rate of Change in C from Forest Biomass and Litter (Northeast Oak/Hickory)
14	Examples of C Estimate Equations IPCC Method – Mineland Soil C From Different Studies - Mineland Soil C Mg C ha^-1 = 15 + 29.5/{1 + exp[– (t – 10.8)/2.39]} SOC = 0.12 t ^0.78 (g 100 g^-1 soil) C from Forest Biomass (Northeast Oak/Hickory) Mg C ha^-1 = 1.79 t ^0.797
15	Range of Annual C Accumulation Rates
16	Average C Accumulation Rates
17	Annual C Accumulation from Land Uses
18	Average Annual C Accumulation
19	Average Annual C Accumulation from Forest
20	Counties with Highest Annual Sequestration Rates
21	Mineland C Sequestration as GHG Off-Set 1990 CO₂ emission estimate for 7 state region: 715 Tg CO₂ yr^-1 C sequestration potential on mineland reclaimed to forest : 1.5 Tg C yr^-1(5.5 Tg CO₂ Eyr^-1) Mineland C storage < 1% of total 1990 CO₂ emissions Mineland C storage = 11% of Kyoto emission reduction requirement (7% below the 1990 level - excluding increase in emissions between 1990 and 2005)
22	Potential Annual C Accumulation and 20 Year Accumulation on Reclaimed Minelands
23	C Accumulation over 20 Years
24	C Accumulation on Minelands over 20 Years
25	Conclusions Reclaiming mineland to forest provides the largest GHG emission off-set Mineland reclaimed to forest represents a viable GHG emission mitigation option Reclaimed mine sites may provide least cost option for GHG mitigation Landowners already planting some mineland to forest Not removing or changing land use Potential income stream from C credits Incentive for landowners to plant forest Motivation for additional research to enhance forest on reclaimed mineland Reclaiming mineland to forest provides ancillary environmental benefits (wildlife habitat, reduced soil erosion, improved water quality, etc.)